Vibration failures always occur in the lead with the exception of badly
wetted solder joints or solder joints thermally fatigue damaged prior to
vibration. In the case of ceramic QFPs on polyimide CTE-restrained to ~7
ppm/C, thus the DCTE->0,   
the solder in the bend is likely to concentrate the stresses even more than
otherwise right at the component body. I suggest testing or FEA analysis. 

Werner Engelmaier
Engelmaier Associates, Inc.
Electronic Packaging, Interconnection and Reliability Consulting
23 Gunther Street
Mendham, NJ  07945
Phone & Fax: 201-543-2747
E-mail: [log in to unmask]

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